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3 Sheets-Sheet 1 xw Q A. LARSON SINTERING MACHINE GRATE Original FiledAug.

March 4, 1924.

March 4 1924.

A. 1.. LARSON SINTERING MACHINE GRATE s Shets-Sheet 2 Original FiledAug.

'hmia: 1Q LLmesa/Y.

March 4, 1924.

A. L. LARSON SINTERING MACHINE GRATE Originai Filed Aug. 20. 1920 5Sheets-Sheet 5 Reisaued Mar. 4, 1924.

UNITED STATES PATENT OFFICE.

AUGUST L. LARSON, OF IIELLOGG, IDAHO, ASSIGNOR TO COE'UB DALE'NEHARDWARE AND FOUNDRY COMPANY, OF WALLACE, IDAHO, A CORPORATION OF IDAHO.

SINTERINGFMACHINE GRATE.

Original 80. 1,873,820, dated April 5, 1921, Serial No. 404,776, filedAugust 20, 1920. Application for reissue filed March 81, 1923. SerialNo. 829,180.

To all whom it may concern:

Be it known that I, AUoUsT L. LARSON, a citizen of the Dominion ofCanada, residing at Kellogg, county of Shoshone, State of Idaho, haveinvented certain new and useful Improvements in sintering-MachineGrates, of which the following is a specification.

This invention has relation to improvements relating to what is known asDwight l0 & Lloyd sintering machines and more particularly has referenceto improvements to that form of grate mechanism embodied in the resentractical application of sintering mac ines oi the type mentioned, knownas the Stewart grate construction, and my invention is specificallydirected to the improved arrangement of the grate bottoms of the palletsor carriers embodied in such grate construction.

It is well known to those familiar with the use of sintering machines,that the modern type of such machines include a lar her, as high asforty-two individua pallets or carriers that travel along endless wayswith the ore contained therein which are subjected, during a part oftheir travel, to

the desulfurizing and sintering operation,

after which, in the return movement and inverted osition, the loads oftreated ore con- 39 tained m the said individual pallet are discharged,the empt pallets traveling back to be again convey to their uppermostposi tion to be again recharged.

In the construction of sintering machines 86 of the general type stated,each pallet has a grated bottom whose members are bolted tightly to thepallet sides and as a result of such attachment, when the grates becomeheated and expansion takes p ace, the grate 40 bars or members do ngtstay in the desired alinement and also, due to the heat of the furnace,clinkers frequently are formed in the slots of the grate surface,thereby atl interfering with the extraction of t e an furic gases. Toovercome this serious objectionable condition, it has been necessary tostation a man at each machine whose duty it was to clean the grates asthe pallets move around the furnace.

so That this defect in the desired or perfect operation of the Dwight 8:Lloyd sintering num-' machine be fully appreciated, it should be stated,by the improper expansion of the grate irons (and by the im r0 erexpansion is meant that the heat of t e urnace causes the grate membersto expand in different directions) which results in the grate slotsbecoming tight on the one side and leaving too muc space at the otherside, and since the ore in the traveling pallet is usually crushed fine,it (the ore) naturally passes through such widened grate slots, oftennecessitating the shovelin of tons of the wasted ore back into the %)insto, be again carried through the roasting process. v

Primarily, my invention has for its object to provide a grateconstruction for pallets of sinterin machines, which is selfcleaning andwhich practically overcomes the improper expansion of the ate irons andthe consequent elimination o the aforesaid ore wastage and extra laborrequired for gathering such wastage for retreatment.

Another and essential feature of my invention is the provision of agrate construction for sinterin machine pallets or ore carriers, in whicthe grate members are particularl desi ed for being economically made,easi y a i ed for use, and employed to a greater a vantage in a numberof respects than can be present in the construction of grate bottoms ofthe character referred to and used in ore treating apparatus.

The preferred embodiment o my invention is illustrated in theaccompanying drawings in which suflicient portions of a sinteringmachine are represented as is necessary to illustrate apracticalapplication of my invention and in which:

Figure 1 is a side elevation of a portion of a sintering or ore roastingmachine, several of the pallets or carriers being shown in operativeposition.

Fig. 2 is a diagrammatic sectional view, which illustrates a number oforeloaded allets positioned as passing across the ore ox of thesintering machine.

Fi 3 is a detail cross section taken on the hne 3-3 of Fig. 2.

Fig. 4 is a plan view of a pallet with my improved constructionetiuippetg o gra bottom.

Fig. 5 is a cross section thereof, the grate bars or irons being at thenormal or load carrying position. l

Fig. 6 is a view similar to Fig. 5, the pallet being shown at a reversedor dumplng position and the movable grate irons at their shifted osition for effecting the self-cleanin of t e iron.

Fig. 7 is a perspective view of one of the end grate bars.

Fig. 8 is a similar view of one ofthe movable grate bars.

Fig. 9 is a perspective view of one of the stationary grate bars.

Fig. 10 is a detail view illustrating the cooperative relation of theclamping bar shown in face view and the assembled grate units, thelatter being shown in end elevation.

Figs. 11, 12, and 13 are detail cross sections taken on the lines'11-11, 12-12, and 1313 on Figs. 7, 8, and 9 respectively.

As before stated, my improved grate construction is especially designedfor constitut ing the'bottom of pallets or carriers that form anessential feature of the Dwight & Lloyd types of sintering machines andthat the 0 erative arrangement of such pallets and their grateconstruction be readi y understood, a sintering machine of the kindstated is diagrammaticall illustrated in Fig. 1 of the drawings an thecooperative arrangement of the members of the pallets or carriers withthe ways on which they travel and the air or suction box over whic theypass is illustrated in Figs-2 and 3 and, in the said Figs. 1, 2, and 3,1 designates the endless track that is arranged to support and directthe series of pallets or carriers 3,

which serve as the su porters for the ore durin the roasting ansintering operation. It s iould be stated, the pallets, in ractice, arecaused to move slowly in the irection indicated by the arrows a,the'means for effecting such direction of movement of the pallets forfeeding the ore to the said pallets and for igniting the ore, afterbeing delivered to the pallets, being readily understood by thosefamiliar with the use of sintering machines of the type mentioned byreferring to Fig. 1, it being also understood that, after the ore hasbeen ignited, it passes with the pallets across the air box 2 and afterpassing from the air box, the said pallets, in their travel, passdownward over a circular path, overturningat such point to dischargewhatever load they may carry, one of the pallets being shown positionedat the discharge point in Fig. 1 and another indicated as returning downthe inclined way toward the other end for being again carried up inposition for reloading in the same figure. The general arrangement of anumber of pallets or carriers, their rates and the man nor of sustainingsuch pa lets on their guides causing a percentage of the ore to passthrough without having the gases properly extracted, the said connectingbars usually requiring six bolts for securing them in place, therebycausing some inconvenience, when it is necessary to remove or replace agrate iron.

Referring now more specifically to the essential features of myinvention, reference is made to Figs. 4, 5, and 6 of the drawings,

'which illustrate a. complete pallet in which is included my improved.construction of grate bars.

The grate bottom, as shown, comprises two fixedly held end grate bars44, two intermediate fixed grate members 55, three movable grate bars66-6 and two connecting bars 77, one of which is located at each end ofthe pallet or box.

-One of the movable grate members 6 mentioned is located between thepair of fixed grate members or bars 5-5 and the other two movablemembers 66 are located between a fixed bar and an end bar at theirrespective sides of the pallet frame, as is best shown in Figs. 2, 4, 5,and 6.

The end bars 4, asalso the intermediate or fixed grate members 6, are oflike construction, one of each of the said end bars, the movable barsand the intermediate fixed bars being shown in detail in Figs. 7, 8, and9, respectively.

It will be noticed by referring to Fig. 5, the adjacent edges 40, 50,and 60 of the several ends, the movable and the fixed grate bars aretapered to allow for a certain amount of play of the movable barssuflicient when the pallet reaches the turning over or d schargingposition, shown in Fig. 6, for dumping the ore, that the jars cause themovable bars to shake in such manner and to leave their normal position,shown in Figs. 2 and 5, and assume the position shown in Fig. 6 that theslots or s aces bet-ween the several grate bars are sel -cleaned and. asthe movable bars 5, in )ractice, fall the distance of about one-half aninch, provides for forcing any ore on the grates, in the form ofclinkeis, out of the grate slots, the ore falling into the proper bin.

In my construction of grate, the several bars 4, 5. and 6 have theirends peculiarly shaped for cooperating with the eoacting edges of theconnecting bars that hold the several bars 4, 5, and 6 down onto theinturned angled flanges 30 of the pallet frame and, in my grateconstruction, there are two of such connecting bars 7, one for each endof the pallet box or frame and for engaging with their respective endsof the grate bar.

Each connecting bar 7, one of'which is shown in detail in Fig. 10, is ofsuflicient length to extend across the full width of the pallet box (seeFig. 4) and it has three bolt holes 70-70-70 for receiving the fasteningbolts 8 and each bolt hole is elongated vertically for adjusting the bar7 to allow for a proper fitting o the connecting bar in connection withthe several fixed grate ars.

The lower edge of each connecting bar 7 is shaped for effecting a simpleand easily fitted adjustment with the eculiarly shaped ends of theseveral grate ars 4, 5, and 6 and for such purpose, the said lower edgehas a pair of pendant tapered lugs 71-71 adapted for seating withintapered sockets 51-51 in the adjacent ends of the grate bar 5, tothereby fixedly hold the said bar 6 down upon the pallet flanges 30-30.

At the opposite sides of the taperin lugs 71-71, the lower edge of .thebar has tapered sockets 72, three of such sockets being provided andmade of sufficient width to allow the bearing faces of the movable gratebars 6 to move therebetween, when the pallet assumes the turned overposition, as indicated in Fig. 6, the slots being tapered in such amanner'to allow plenty of play for the movable grates.

To provide a close fitting of the connecting bar 7 and also for holdinthe end grate bars as an integral art 0 the complete grate structure, sot at, under expansion and contraction, all of the grate members movetogether, the opposite ends ofthe con-" nee-ting bar are of greaterdepth than the other parts there0f,'by reason of the luglike' extensions73-73 that fit down into off-sets 40-40 in the ends of the bars 4-4,

which ends are also beveled, on their top surface, as at 41, for theclose fitting of the tapering edges of the end sockets into which theoutermost ones of the movable bars enter, as they drop from betweentheir adjacent end and fixed grate members.

One of the essential features in my grate construction, is he means forholding the specified grate bars from expanding irregularly and for suchpurpose, each of the fixed and the end grate bars, which latter are alsorelatively fixed bars, at the opposite sides of their ends, havevertical ribs 9 that taper from the widest or head portion, at the topface of the grate, to a V- iaped ending at tbe'bottom of the bar and thesaid ribs 9 on the said bars 4 and 5 are adapted for extending into likeshaped vertical the other side.

grooves 10-10 on the adjacent edges of the movable bars 6, the taperedform of the ribs 9 and the grooves 10 permitting of free movement of thebars 5 with res t to the other bar and reduces frictional, inding ofsuch parts.

By providing positive contacting points between all of the grate barsthat constitute the complete set of grate bars and arranged in themanner described and shown, when the grate irons begin to expand, underthe heat of the furnace, causes the entire pallet (all of the partsthereof. being relatively in contact) to expand the same way and therebyreduces to the minimum danger of the grate irons expanding in differentdirections, the closing of the slots at one side and excessive wideningof other slots at The means for holding the several gra bars in proper oerative position on the pallet flanges 30 (t e connectin bar 7) is suchthat the removal of the said %ars is rendered simple and may bequickly-effected and also renders it very convenient for removing andreplacing a grate bar, when necessary.

While this description is directed to a grate for the Dwight & Lloydtype of sintering apparatus, my improv grate is equ'ally' useful in anintermittent type of apparatus wherein the sinterin pan is rotated aboutits own axis. Furt ermore, my invention need not be restricted to the scific grate herein described, since any rel tive movement of the gratebars resulting in a distortion of the grate surface is broadlycontemplated. It follows from the foregoing that the distorting of thegrate surface,'or the bringin of different portions of said surface intoifl'erent planes so as to destroy the evenness of that surface with thedumping of the pan, or treatment vessel, constitutes the principalfeature of my invention.

Having described my invention, I claim:

1. In a grate for ore carriers or pallets, a series of relativelyfixedly held grate irons and other grate irons cooperative with thefixedly held irons and movably mounted with respect to the said fixedlyheld irons and havln a limited outward drop relatively to t 1e fixedlyheld arms, as the pallet or carrier is inverted.

2. In combination with a pallet frame having an inwardly extendedbearing flange along each of its ends of a grate construction thatcomprises a number of relatively fixedly held bars and a movable barlocated between each pair of adjacent fixedly held bars and means alongthe ends of the pallets for limiting the outward movement of the saidmovable (grate bars as the pallet assumes a turne over position. I

3. In an ore carrying pallet for sintering machines, the combinationwith a bearing flange 'aI ngeachpitheopposite endaofitlge pallet-f ame;afsi ri .ietsa tema e y dis: posed-relatively fixedly @l'ield-,grateiharswhav ing their Opposite endssliaped.;t;o; res t;uponthe-aforesaid flanges, other; grate ba-rs :intermediate the relativelyfixedly held,- bars having their ends; shaped -.to-rest ;upo the saidend flanges of the pallet-frame and having-movement outwardly,withresjpectf to the said relatively fixedly held grate bars, and meansattachable to each-ofthepallet ends adapted forengagement with the endsof the several relatively fixedly held bars and provided with stopportions for limiting the outward thrust of the movable bars, as thepallets assume a turned over'position.

4. In a sintering machine pallet, a grate that constitutes the bottom ofthe pallet, the said grate being composed of pairs of-relatively fixedlyheld grate bars and other bars, one of said other bars intermediate eachpair of the relatively fixedly held bars,

the said other bars having movement vertically between the said fixedlyheld bars, as the pallet assumes the turned over position, and means oneach of the opposite ends of the pallet for limiting the outward drop ofthe said movable bar and for holding the other bars to their relativelyfixed position.

5. In a sintering machine allet, a grate bottom including a series of reatively fixedly held bars and a series of other bars intermediate therelatively fixedly held bars, the said intermediate bars having verticalmovement between the other bars, as the pallet turns over, the saidmovable and fixedly held bars having relatively slidable contactingportions at the opposite edges at each of their opposite ends for thepurpose stated.

6. In a grate construction for sintering machine pallets, thecombination with the pallet frame having an inturned bearing flangealong the opposite sides and ends, a pair of end grate bars that engagethe side and end portions of the pallet flange, a plurality ofintermediate grate bars whose opposite ends terminate in narrowextensions for resting upon the op osite flanges at the opposite ends ofthe pal et, other rate bars tween each pair of the interme iate gratebars and between the intermediate grate bars and the adjacent end bars,the said intermediate bars having reduced end extensions for resting onthe end flanges of the pallet frame, and connecting bars removablyattachable one to each pallet end, the said bars having their lower edgeshaped for positively engaging the end extensions of the end and theintermediate bars, whereby to fixedly hold the said bars onto the palletflange bearings and provided with socket portions that fit over the endextensions of the aforesaid other bars between the fixedly held bar,whereby to rovide for a limited out-ward movement 0? the said other barsole-1a be ween their djac nt: bars for-- di dgi g elin-ker's :andjthelike, asthe pallets assume theirturned nav l;'p-eaitio 7. Aagrateconstruction for sintering machine pallets, comprising.two end bars, twofixed bar-s,,a--Ino-vable bar between each end and an adjacent fixedbar, another movable bar betweenthe fixed bars and means for securingthe several barsin their fixed and movable relation within the palletframe, the said means comprising an internal bearing flange along eachof the opposite ends of the pallet frame, and a connecting bar removablyattachable to each end of the pallet frame with the lower edgepositively engaged with the end and the fixed bars and having socketportions that fit over the adjacent ends of each of the movable bars. 8.A grate construction for sintering machine pallets, comprising two endbars, two fixed bars, a movable bar between each end and an adjacentfixed bar, another movable bar between the fixed bars and means forsecuring the several bars in their fixed and movable relation within thepallet frame, l

the said means comprisino' an internal bearing flange along each of theopposite ends of the pallet frame, and aconnectin bar re- Dvablyattachable to each end 0 the pal let frame with the lower edgepositively engaged with the end and the fixed bars and having socketportions that fit over the adjacent ends of each of the movable bars,and means tending to constantly hold all of the grate bars in edgewisecontact with each other and with the pallet frame to thereby cause theentire pallet to expand together.

9'. A grate construction for sintering machine pallets, comprising twoend bars, two fixed bars, a movable bar bet-ween each end and anadjacent fixed bar, another movable bar between the fixed bars and meansfor securing the several bars in their fixed and movable relation withinthe pallet frame, the said means comprising an internal hearing flangealong each of the opposite ends of the allet frame, and a connecting barremovab y attachable to each end of the pal let frame with the loweredge positively engaged with the end and the fixed bars and havingsocket portions that fit over the adjacent ends of each of the movablebars, and means tending to constantly hold all of the grate bars inedgewise contact with each other and with the pallet frame and therebycause the entire pallet to expand togather, the said means including't-apered' ribs and coengaging grooves along the'meeting edges of eachpair of grate bars, whereby constant contact between the several movableand fixedly held bars is maintained, as the movable bars work outwardpasses to the ore umping position.

10. In a grate construction for sintering machine pallets, thecombination with the pallet frame and a set of relatively fixed gratebars, of a second set of ate bars adapted to be moved bodily out 0 theplane of the first series ofbars to dislodge the contents of the-pallet.

11. In a sinterin machine wherein is provided a series of a lets andmeans for moving said pallets in a train through a continuous path andinverting the allets to discharge the load, a set of pal et grates foreach pallet, each comprising a set of fixed bars and a set of movablegrate bars and means for limiting the motion of said movable bars to adirection substantially at right angles to the plane of the grate tothereby dislodge the contents of the pallets upon inversion thereof.

12. In combination with a treatment vessel, a grate presenting asubstantially even surface for the support of the charge to be treated,said vessel being tiltable for dumping the charge, and means forcausing-a distortion of the charge-supporting surface of the grate withadumping movement of the vessel.

13. In combination with a treatment vessel tiltable in a vertical planeabout a fixed axis, a grate presenting a substantially even surface forthe support of the charge to be treated, and means for causing adistortion of the charge-supporting surface of the grate with a tiltingof the vessel to dumping position.

14. A grate of the character described, comprising a series of componentmembers forming a support for the charge, and means for ermitting amember to participate in a limited outward movement from its normalposition of rest.

15. In a grate of the character described, comprising a series ofcomponent members forming a support for the charge, and means forpermitting a member to partici pate in a limited outward movement in adirection transverse to the supporting surface of the grate.

16. A grate of the character described, comprising a series of componentmembers collectively presenting a normally horizontal supporting surfacefor the charge, and means for permitting a member to participate in alimited vertical outward movement. a

17. A' grate of the character described, comprising a series ofcomponent members collectively forming a support for the charge, saidgrate being provided with openings for the passage of gases, and meansfor permitting a miember to participate in a limited outward movement ina direction transverse to. the supporting surface of the grate.

18. A grate of the character described,

mounted to be inverted for dumpin comprising a series of grate-barsspaced suitable distances apart to form grate openings, means forsupportin the bars, and means for permitting a pre etermined number ofthe bars to participate in alimited outward movement in a directiontransverse to the supporting surface of the grate.

19. In combination with a sintering pan rotatable in a vertical planefor dumping the charge treated, supporting means positioned beneath thecharge during the period of treatment, said supporting meansparticipating in a limited downward movement to break up and dislodgeany sintered material adhering thereto upon rotation of the pan todumping position.

20. In combination with a sintering pan tiltable in a vertical plane fordumping the a charge treated, a support for the char and means forcausing said support to shift its position within suitable limits with adumping movement of the pan, in a direction operating to release anysintered material adhering to the support.

21. In combination with a sintering pan mounted to be inverted fordumping the treated charge, a series of supports for the charge, andmeans for causing a predetermined portion of said supports to become dislaced from their normal positions of rest wit an inversion of the .pan,said dis lacement being in a direction operating to leak up and releaseany sintered material adhering to said supports.

22. In combination with a sintering pan tiltable'in a vertical plane forpurposes of dumping, a grate for supporting the charge during treatment,said grate-having component parts capable of a limited verticalmovement, and means cooperating with said parts to cause a verticaloutward displacement thereof from their normal positions of rest with adumping movement of the pan, thereby dislodgmg and breaking up any.sinter adhering to the grate.

23. In combination with a grate-bar, a suitable su port for the bar, andcooperating means etween the bar and its support for causing the bar todrop a certain distance with an inversion of the bar and its support.

24. In combination with a sintering pan the treated charge, supportingmeans positioned beneath the charge during the period of treatment, saidsupporting means participating at different points in a limited downwardmovement to break up and dislodge any sintered material adheringthereto, upon the tilting of the pan to dumping osition.

25. In combination with a tiltab e treatment vessel, a grate memberpositioned to support the charge and being at rest during the treatmentof the charge, and means for causing said member to drop through alimited distance away from its normal position of rest, with a dumpingmovement of the vessel.

26. In combination with a tiltable treatment vessel, a perforatedsupport'for the charge, and means for causing different portions of saidsupport to drop through a limited distance away from their originalpositions of rest with a dumping movemen of the vessel.

27. In combination with a tiltable sintering pan, a grate comprising aplurality of independent members for supporting the charge, and meansfor causing a portion of the members to participate in a limiteddownward displacement from their original supporting positions with adumping movement of the pan.

28. In combination with an open top; sintering pan rotatable about afixed axis for dumping, a grate com risinga plurality of bars spacedapart ant collectively presenting an even supporting surface to thecharge resting thereon, and means for causing a portion of the bars toparticipate in a limited drop with a dumping movement of the pan;

29. In a tiltable treatment vessel, a grate comprising a plurality ofmembers spaced apart, and means for imparting to any predeterminednumber of the members a llmited outward displacement in a directlontranverse to the charge-supporting surface of the grate with a dumpingmovement of the vessel.

30. In combination with a treatment vessel tiltable in a vertical plane,a grate member participating in a limited outward movement or drop witha tilting of the vessel to dumping position.

31. In combination with a tiltable treat ment vessel, a grate comprisinga series of component members forming a support for the charge, andmeans for causing a member to'participate in a limited outward movementfrom its normal position of rest with a tilting of the vessel to dumpingposition.

Signed this 24th clay of March, 1923.

AUGUST L. LARSON.

